1. Technical Field
The present invention relates to a printing apparatus and a printing method. Particularly, the invention relates to a printing apparatus and a printing method which perform a transportation of a printing medium for performing an attachment of liquid to the other surface of the printing medium after performing the attachment of liquid to one surface of the printing medium.
2. Related Art
In recent years, many printing apparatuses such as printers have been equipped with a double-sided printing mechanism, and the most-widely used double-sided type printer is a type on which a recording head and a paper reversing mechanism are mounted. In such a printer, after printing one surface of the printing paper by a recording head, a front and a back of the printing paper are reversed by passing through a predetermined transport path, thereby also performing the printing of the other surface by the same recording head.
Herein, when ink is attached to the printing paper and the printing paper absorbs ink, since the surface of the printing paper swells but a site other than the printing paper surface does not swell significantly, it is known that a phenomenon (hereinafter, also referred to as a “swelling curl”) is generated which causes a warpage such as an expansion of the surface the printing paper. The paper, in which the swelling curl is generated, may come into contact with a member in the printer when being transported in the printer and there is a concern that the printing quality may be adversely affected (an abrasion, dirt, a paper folding or the like).
In order to avoid the adverse affect on the print quality, in the related art, largely two types of measure have been taken. A first measure is to alleviate the swelling curl of the printing paper by performing a forced drying or the like using a drying delay and a warm air heater before the printing of the back when the printing to the front is finished (for example, see JP-A-2000-1010). A second measure is to provide a mechanism which gives a warpage of an opposite direction to the warpage of the swelling curl to the printing paper to forcibly remove the warpage of the swelling curl (hereinafter, referred to as a “decurl”).
However, the swelling curl is generated in a site in which the printing is performed, but the technique mentioned above does not consider which site of the printing paper is printed. Furthermore, a degree of the swelling curl fluctuates depending on an amount of moisture contained in ink and an amount of ink attached to each site of the paper, but, the technique mentioned above does not consider the amount of ink attached to each site of the printing paper.
Furthermore, even when the drying waiting is performed, it is difficult to reliably decurl the swelling curl, and thus the drying and waiting are insufficient as measures for the swelling curl. Furthermore, even when the drying is performed by the warm air heater, it is difficult to reliably decurl the swelling curl, and thus the warm air heater is insufficient as a measure for the swelling curl. Furthermore, when separately providing a mechanism for decurl, the cost is increased and a design is changed, and there is a need for an extra space that accommodates the mechanism.